JP2000065732A - Surface plasmon resonance angle detection device, and sample temperature control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an SPR angle detection device capable of accurately detecting the resonance angle by making constant the temperature of a sample solution in a flow cell, and a sample temperature control method and to provide an SPR angle detection device capable of reducing the detection cost by detecting the resonance angle for a long time with improved chemical resistance, and a sample temperature control method. SOLUTION: The SPR angle detection device 1 applies light from a light source 23 to a sample solution being provided at a sensor chip where a prism 5 is bonded to a surface in that no metal thin film is provided in a glass substrate 21 where a metal thin film is formed at a required incidence angle width, detects a resonance angle based on the reflection light intensity from the metal thin film, and specifies a sample constituent. In a cell block being bonded to the metal thin film side of the glass substrate 21, a flow cell is formed opposite to the metal thin film, and at the same time, a temperature detection member 17 for detecting the temperature of the cell block at a part close to the flow cell and a heating member 19 for heating a sample solution in the flow cell by heating the inside of the cell block are mounted. The sample temperature is maintained uniformly by heating and controlling the heating member 19 based on the temperature of the cell block near the flow cell being detected by the temperature detection member 17.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface plasmon resonance angle detecting apparatus for irradiating a sample solution on a glass substrate on which a metal thin film is formed with light to specify its component by the resonance angle at which the reflection intensity is minimized. (Hereinafter referred to as SPR detector)
The present invention relates to a temperature control mechanism and a control method provided therefor.

[0002]

In the sensor chip of the SPR detector, at least one of a metal film and a silver thin film is formed on the surface by any one of an ion plating method, a sputtering method and a vapor deposition method. The prism is closely attached to the glass substrate, and the cell block having the flow cell is closely attached to the glass substrate on the side of the metal thin film, and the sample solution is pumped into the flow cell and filled with the sample solution. The light or spot light converging on the surface is incident at a required angle width (35 to 80 °), and the reflected light from the metal thin film boundary is received by a light receiving member such as a CCD or a photodiode array to minimize the reflected light intensity. That is, the component of the sample is specified by detecting the resonance angle at which the absorbance of the sample solution becomes maximum.

However, when the resonance angle is detected by the above-described method, the refractive index of light greatly changes depending on the temperature of the sample solution. Therefore, in order to accurately detect the resonance angle, it is necessary to maintain the temperature of the sample solution constant. was there.

After the detection of the resonance angle, prior to detecting another sample component, the sample adhered to the flow cell, the supply-side and discharge-side channels connected thereto, and the metal thin film is washed with hydrochloric acid or the like. Therefore, the cell block is required to be made of a material having excellent chemical resistance.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned conventional drawbacks, and an object thereof is to accurately detect the resonance angle of a sample solution in a flow cell while keeping the temperature constant. It is an object of the present invention to provide an SPR detection device and a sample temperature control method capable of performing the above-described steps.

Another object of the present invention is to provide an SPR detection apparatus and a sample temperature control method which are excellent in chemical resistance, enable long-term resonance angle detection, and can reduce the detection cost. .

[0007]

[Means for Solving the Problems] Therefore, claim 1
By irradiating light from a light source at a required incident angle width to a sample solution provided on a sensor chip in which a prism is adhered to a surface of a glass substrate on which a metal thin film is formed, where the metal thin film is not provided. In a surface plasmon resonance angle detection device that detects a resonance angle based on the intensity of light reflected from a metal thin film and specifies a sample component, a cell block that is in close contact with the metal thin film side of the glass substrate has a flow cell that faces the metal thin film. It is characterized by comprising a temperature detecting member formed and detecting the temperature of the cell block at a position close to the flow cell, and a heating member for heating the sample solution in the flow cell by heating the temperature in the cell block.

The heating member is controlled to be heated based on the temperature of the cell block near the flow cell detected by the temperature detecting member to keep the sample temperature uniform.

[0010] Further, a second aspect of the present invention provides a glass substrate on which a metal thin film is formed, wherein a light from a light source is applied to a sample solution provided on a sensor chip in which a prism is adhered to a surface on which the metal thin film is not provided. In a surface plasmon resonance angle detection device that irradiates with a required incident angle width, detects a resonance angle based on the intensity of reflected light from the metal thin film, and specifies a sample component,
The cell block adhered to the metal thin film side of the glass substrate forms a flow cell relative to the metal thin film and heats the temperature inside the cell block with a temperature detecting member for detecting the temperature of the cell block at a location close to the flow cell. A heating member that heats the sample solution in the flow cell, and controls the heating of the heating member based on the temperature of the cell block near the flow cell detected by the temperature detection member to keep the sample temperature uniform. Control.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view schematically showing the SPR detection device. FIG. 2 is an enlarged sectional view of the sensor chip.

First, an outline of the SPR detecting device 1 will be described. A prism holder 3 made of a metal or synthetic resin and having a quadrangular prism shape is attached to a frame (not shown) of the SPR detecting device 1. The holder 3 is formed with a shaft support hole 3a having an axis in the vertical direction shown in the figure. or,
A support recess 3b for supporting a half-cylindrical prism 5 is formed in the upper central portion of the prism holder 3, and an optical path is formed in the prism holder 3 corresponding to the light incident side and the emission side of the support recess 3b. 3c and 3d communicate with the outside and are formed symmetrically. The path width of each of the light paths 3c and 3d is such that the angles of incidence and exit of light with respect to the prism 5 are 35 to 80 degrees and 100 degrees, respectively.
It is set to be in the range of １４145 degrees.

A cylindrical body 7 whose upper and lower sides are opened is attached to the upper part of the prism holder 3, and a cell block 9 is supported in the cylindrical body 7 so as to be slidable in the vertical direction. The cell block 9 is made of a metal material such as stainless steel, which has excellent chemical resistance and good thermal conductivity, and a lower surface of the cell block 9 is provided with a pair of guide rods 11 supported by the shaft support holes 3a. The upper part is fixed. A fixing plate 13 is attached to the end of the guide rod 11 protruding from the lower surface of the prism holder 3, and each guide rod 11 located between the fixing plate 13 and the lower surface of the prism holder 3 has a compression spring or the like. The elastic member 15 is attached, and each elastic member 15
The cell block 9 is pressed against the upper surface of the prism holder 3 by the elastic force of the above.

At the center of the lower surface of the cell block 9, a flow cell 9a having a substantially elliptical plane is formed.
The supply flow path 9 is provided in the cell block 9 corresponding to the long-axis-side end portion a.
b and the discharge channel 9c are formed respectively. A sensor mounting hole 9d is formed at the center of the cell block 9 at a depth close to the flow cell 9a, and a temperature sensor 17 such as a thermocouple or a resistance change type temperature sensor is mounted in the sensor mounting hole 9d. Have been. The temperature sensor 17 detects the temperature of the sample solution in the flow cell 9a. Further, a heating member 19 such as a sheet heater or a Peltier element is attached to the outer surface of the cylindrical body 7, and the heating member 19 is ON-OFF controlled based on the temperature near the flow cell 9a detected by the temperature sensor 17. The temperature of the sample solution in the flow cell 9a is kept almost constant.

A glass substrate 21 is mounted between the upper surface of the prism 5 and the lower surface of the cell block 9 so as to be in close contact with each other. On the upper surface of the glass substrate 21 on the cell block 9 side, a metal thin film (not shown) is formed by an ion plating method, a sputtering method, or a vapor deposition method at least in a size substantially coinciding with the flow cell 9a. An antibody, a reagent, and the like for detecting a specific substance of the sample solution are fixed on the metal thin film of the glass substrate 21 in advance.

A light source 23 is arranged on a frame corresponding to the light path 3c on the incident side, and a light receiving member 25 is arranged on a frame corresponding to the light path 3d on the emission side. The light source 23 may irradiate the prism 5 with light converging at the boundary surface of the metal thin film of the glass substrate 21 with the above-mentioned incident angle width or variably enter spot light at the above-mentioned angle. The light receiving member 25 receives light having the above-mentioned angular width, for example, CC.
The intensity of the reflected light from the glass substrate 21 is detected at each angle by D, a photodiode array, or the like.

A sample supply adapter 27 is connected to the supply channel 9b of the cell block 9, and a sample discharge adapter 29 is connected to the discharge channel 9c via pipes 31 and 33, respectively. In the sample supply adapter 27, a mounting portion 27a into which a tip (not shown) of a known micropipette used for dispensing a sample solution in an analysis operation is formed so as to communicate with the pipe 31. Have been. A micropipette is basically a cylinder structure (syringe structure), and variably adjusts a piston stroke according to the amount of suction, and aspirates and discharges a sample solution at a constant rate. The tip of the micropipette is made of an elastic material such as silicone rubber and has a sharp conical shape, and when inserted into the mounting portion 27a, is elastically deformed and adheres to the tapered surface.

On the other hand, a conical mounting portion 29a slightly larger than the mounting portion 27a of the sample supply adapter 27 is formed in the sample discharge adapter 29 so as to communicate with the pipe 33. The mounting portion 29a supplies the sample solution to the flow cell 9a. As a result, the sample solution overflowing from the flow cell 9a and the washing liquid pushed out from the inside of the flow cell 9a are stored.

Next, the operation of the SPR detection device will be described.

A predetermined amount of the sample is operated by operating the lever of the micropipette in a state where the tip of the micropipette whose piston stroke is adjusted in accordance with the amount of the sample solution to be aspirated is pressed into the mounting portion 27a and brought into close contact therewith. The solution is filled in the flow cell 9a via the pipe 31 and the supply channel 9b. At this time, since the mounting portion 27a and the chip 35 are in close contact, air is prevented from being mixed into the sample solution filled in the flow cell 9a. The flow cell 9a
The sample solution overflowing from the inside is stored in the mounting portion 29a via the discharge channel 9c and the pipe 33.

In this state, the control means (not shown) reads the temperature around the flow cell 9a by the temperature sensor 17 every predetermined sampling time, and when the temperature is lower than a predetermined temperature, the control means turns on the heating. The member 19 is turned on to heat the cell block 9. Then, when the temperature around the flow cell 9a by the temperature sensor 17 reaches a predetermined temperature, the control means turns off the heating member 19 and outputs a detection permission signal, for example, by turning on a display lamp (not shown). Is notified that the detection of the resonance angle of the sample by the SPR detection device 1 has been enabled. Note that, without turning on the display lamp, the light may be automatically emitted from the light source 23 and the intensity of the reflected light may be detected by the light receiving member 25 to detect the resonance angle.

The heating method by the heating member 19 includes the flow cell 9a detected by the temperature sensor 17.
What is necessary is just to control so that the cell block 9 is heated by applying a heating pulse of a preset pulse number or duty to the heating member 19 according to the difference between the ambient temperature and the predetermined temperature.

Next, when the operator turns on the start switch of the SPR detector 1, the light source 23 emits light of a required angular width converging toward the metal thin film boundary surface of the glass substrate 21, or the light source 23 is turned into a prism. The spot light is emitted toward the above boundary while rotating an arc along the outer circumference of 5 at a required angle width, and the reflected light intensity is minimized based on the reflected light intensity received by the light receiving member 25. Therefore, the flow cell 9a The angle at which the absorbance with respect to the sample solution in the sample is maximized is detected as the resonance angle of the sample. Then, the operator specifies the components of the sample based on the resonance angle.

When the washing switch (not shown) is turned ON to detect the resonance angle of another sample after the above-mentioned resonance angle is detected, the pipe 31 is switched to the washing liquid pan (not shown) by the electromagnetic valve, for example, hydrochloric acid. The cleaning liquid or cleaning water such as the pipe 31, the supply flow path 9b, the flow cell 9a, and the discharge flow path 9
(c) The sample solution supplied to the pipe 33 and attached to the metal thin film is washed. At this time, since the cell block 9 is made of a metal material such as stainless steel having chemical resistance, corrosion by the cleaning liquid can be prevented.

In this embodiment, the temperature of the sample solution in the flow cell 9a is detected by a temperature sensor 17, and if the temperature is not a predetermined temperature, the heating member 19 causes the cell block 9 to be heated.
Is heated to bring the sample solution stored in the flow cell 9a to a constant temperature, and then the resonance angle is detected. Therefore, the refractive index of the sample solution can be made substantially constant and the resonance angle can be accurately detected.

[0025]

As described above, according to the present invention, the temperature of the sample solution in the flow cell is kept constant, and the resonance angle can be accurately detected. Another object of the present invention is to be able to detect the resonance angle over a long period of time with excellent chemical resistance and reduce the detection cost.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view schematically showing an SPR detection device.

FIG. 2 is an enlarged sectional view of a sensor chip.

[Explanation of symbols]

1 SPR detector, 5 prism, 17 temperature detecting member, 19 heating member, 21 glass substrate, 23 light source

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Haruo Tajima 20-9, Sanbonmatsu-cho, Atsuta-ku, Nagoya Japan Laser Electronics Co., Ltd. (72) Inventor Hiroyuki Nakamura 1-1-1, Ichigaga-cho, Shinjuku-ku, Tokyo No. 1 Inside Dai Nippon Printing Co., Ltd. (72) Koji Sato, Inventor 1-1 1-1 Ichigaya Kagacho, Shinjuku-ku, Tokyo Tokyo, Japan Inside (72) Ryohei Nagata 1-chome, Ichigaya-cho, Shinjuku-ku, Tokyo No. 1-1 F-term in Dai Nippon Printing Co., Ltd. (reference) 2G057 AA01 AB09 AC01 AD17 BA05 BB01 BB08 DA03 DA20 DC01 DC07 EA01 EA06 GA01 GA05 GA06 2G059 AA01 AA05 BB04 DD12 DD13 DD16 EE01 EE02 FF03 JJ12 JJ02 KK04 MM05

Claims (2)

[Claims] 1. A method according to claim 1, wherein a light from a light source is incident on a sample solution provided on a sensor chip in which a prism is adhered to a surface of the glass substrate on which the metal thin film is not formed. In a surface plasmon resonance angle detection device that irradiates with a width and detects the resonance angle based on the reflected light intensity from the metal thin film to specify the sample component, the cell block that is in close contact with the metal thin film side of the glass substrate is A temperature detecting member for detecting the temperature of the cell block at a position where the flow cell is formed in proximity to the flow cell and a heating member for heating the sample solution in the flow cell by heating the temperature in the cell block; The heating temperature of the heating member is controlled based on the temperature of the cell block near the flow cell detected by the detection member to maintain the sample temperature uniform. Surface plasmon resonance angle detecting device. 2. A method according to claim 1, wherein a light from a light source is incident on a sample solution provided on a sensor chip having a prism adhered to a surface of the glass substrate on which the metal thin film is not formed. In a surface plasmon resonance angle detection device that irradiates with a width and detects the resonance angle based on the reflected light intensity from the metal thin film to specify the sample component, the cell block that is in close contact with the metal thin film side of the glass substrate is A temperature detecting member for detecting the temperature of the cell block at a position where the flow cell is formed in proximity to the flow cell and a heating member for heating the sample solution in the flow cell by heating the temperature in the cell block; The heating temperature of the heating member is controlled based on the temperature of the cell block near the flow cell detected by the detection member to maintain the sample temperature uniform. Fee temperature control method.